In those geographical areas which receive any appreciable amount of snow in the winter season, individuals who must perform personal snow clearing operations, such as on sidewalks and private driveways, have typically relied upon snow shovels for manual removal of snow. Such snow shovels have been designed with various styles and materials to attempt to overcome the single greatest detriment of snow removal by shoveling, which is the undue force necessary to lift and remove snow by shovel which force must be communicated through the lower torso of the individual performing the snow clearing operation with the resulting inefficiency of snow removal and the risk of physical injury particularly to the lower torso, or more seriously, the risk of exceeding the cardiovascular condition of the operator.
The prior art has attempted to overcome the deficiency of shovels in snow removal operations performed manually.
As early as 1895, a snow shovel was disclosed in U.S. Pat. No 543,910 which had two handles and a surface which is held at a 45 degree angle to the ground for the accumulation of snow for removal.
A more vertically rectangular snow removal board is illustrated in Design Pat. No. 200,244, as well as the related Utility Pat. No. 3,440,741, wherein a rectangular board is fitted with two angled handles for manual operation and a plate is provided at the ground bearing edge of the board to assist in elevation of the board off the ground when containing snow.
U.S. Pat. No. 4,245,411 discloses a manual scoop type snow pusher/lifter which recites some of the advantages of pushing snow during a removal operation rather than lifting snow.
U.S. Pat. No. 4,516,799 discloses a snow removal implement having a polygonal body with two hand inserts which provides a method for snow removal apparently requiring a tricky move employing two hands and a free foot to fling snow to the side of the cleared area while balancing on a remaining foot.
U.S. Pat. No. 4,607,872 discloses a snow removal device comprising a board of hard but resilient material having hand holds on its uppermost side that are used in conjunction with hand holds on its lateral sides.
U.S. Pat. No. 4,796,367 discloses a manual snow plow which is pulled rather than pushed and has an adjustably displaced V-shaped surface for pushing snow to the side of the line of attack in the snow removal operation.
Additional prior art of general interest include: U.S. Pat No. 967,270; U.S. Pat. No. 2,613,977; U.S. Pat. No. 3,035,816; U.S. Pat. No. 2,891,330; U.S. Pat. No. 4,199,181; U.S. Pat. No. 4,302,894; U.S. Pat. No. 4,547,011; and U.S. Pat. No. 4,669,206.
Despite the fact that the prior art has improved upon the common snow shovel for snow removal operations conducted manually by an individual, the prior art has failed to provide a successful snow removal device which can be adjusted to the job to be performed or the individual capabilities of the manual operator of the snow removal device. Additionally, the prior art has not made provisions for meaningful amounts of assistance of a mechanical nature in snow removal or ease in passing a snow removal device over a surface to be cleared. The present invention, set forth below in greater detail, overcomes these disadvantages of the prior art as will be more adequately set forth below.